1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2009 The FreeBSD Foundation
5 *
6 * This software was developed by Ed Schouten under sponsorship from the
7 * FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 #include <sys/refcount.h>
36 #include <sys/systm.h>
37
38 #include <dev/vt/vt.h>
39
40 static MALLOC_DEFINE(M_VTFONT, "vtfont", "vt font");
41
42 /* Some limits to prevent abnormal fonts from being loaded. */
43 #define VTFONT_MAXMAPPINGS 65536
44 #define VTFONT_MAXGLYPHS 131072
45 #define VTFONT_MAXGLYPHSIZE 2097152
46 #define VTFONT_MAXDIMENSION 128
47
48 static uint16_t
vtfont_bisearch(const vfnt_map_t * map,unsigned int len,uint32_t src)49 vtfont_bisearch(const vfnt_map_t *map, unsigned int len, uint32_t src)
50 {
51 int min, mid, max;
52
53 min = 0;
54 max = len - 1;
55
56 /* Empty font map. */
57 if (len == 0)
58 return (0);
59 /* Character below minimal entry. */
60 if (src < map[0].vfm_src)
61 return (0);
62 /* Optimization: ASCII characters occur very often. */
63 if (src <= map[0].vfm_src + map[0].vfm_len)
64 return (src - map[0].vfm_src + map[0].vfm_dst);
65 /* Character above maximum entry. */
66 if (src > map[max].vfm_src + map[max].vfm_len)
67 return (0);
68
69 /* Binary search. */
70 while (max >= min) {
71 mid = (min + max) / 2;
72 if (src < map[mid].vfm_src)
73 max = mid - 1;
74 else if (src > map[mid].vfm_src + map[mid].vfm_len)
75 min = mid + 1;
76 else
77 return (src - map[mid].vfm_src + map[mid].vfm_dst);
78 }
79
80 return (0);
81 }
82
83 const uint8_t *
vtfont_lookup(const struct vt_font * vf,term_char_t c)84 vtfont_lookup(const struct vt_font *vf, term_char_t c)
85 {
86 uint32_t src;
87 uint16_t dst;
88 size_t stride;
89 unsigned int normal_map;
90 unsigned int bold_map;
91
92 src = TCHAR_CHARACTER(c);
93 if (TCHAR_FORMAT(c) & TF_CJK_RIGHT) {
94 normal_map = VFNT_MAP_NORMAL_RIGHT;
95 bold_map = VFNT_MAP_BOLD_RIGHT;
96 } else {
97 normal_map = VFNT_MAP_NORMAL;
98 bold_map = VFNT_MAP_BOLD;
99 }
100
101 if (TCHAR_FORMAT(c) & TF_BOLD) {
102 dst = vtfont_bisearch(vf->vf_map[bold_map],
103 vf->vf_map_count[bold_map], src);
104 if (dst != 0)
105 goto found;
106 }
107 dst = vtfont_bisearch(vf->vf_map[normal_map],
108 vf->vf_map_count[normal_map], src);
109
110 found:
111 stride = howmany(vf->vf_width, 8) * vf->vf_height;
112 return (&vf->vf_bytes[dst * stride]);
113 }
114
115 struct vt_font *
vtfont_ref(struct vt_font * vf)116 vtfont_ref(struct vt_font *vf)
117 {
118
119 refcount_acquire(&vf->vf_refcount);
120 return (vf);
121 }
122
123 void
vtfont_unref(struct vt_font * vf)124 vtfont_unref(struct vt_font *vf)
125 {
126 unsigned int i;
127
128 if (refcount_release(&vf->vf_refcount)) {
129 for (i = 0; i < VFNT_MAPS; i++)
130 free(vf->vf_map[i], M_VTFONT);
131 free(vf->vf_bytes, M_VTFONT);
132 free(vf, M_VTFONT);
133 }
134 }
135
136 static int
vtfont_validate_map(vfnt_map_t * vfm,unsigned int length,unsigned int glyph_count)137 vtfont_validate_map(vfnt_map_t *vfm, unsigned int length,
138 unsigned int glyph_count)
139 {
140 unsigned int i, last = 0;
141
142 for (i = 0; i < length; i++) {
143 /* Not ordered. */
144 if (i > 0 && vfm[i].vfm_src <= last)
145 return (EINVAL);
146 /*
147 * Destination extends amount of glyphs.
148 */
149 if (vfm[i].vfm_dst >= glyph_count ||
150 vfm[i].vfm_dst + vfm[i].vfm_len >= glyph_count)
151 return (EINVAL);
152 last = vfm[i].vfm_src + vfm[i].vfm_len;
153 }
154
155 return (0);
156 }
157
158 int
vtfont_load(vfnt_t * f,struct vt_font ** ret)159 vtfont_load(vfnt_t *f, struct vt_font **ret)
160 {
161 size_t glyphsize, mapsize;
162 struct vt_font *vf;
163 int error;
164 unsigned int i;
165
166 /* Make sure the dimensions are valid. */
167 if (f->width < 1 || f->height < 1)
168 return (EINVAL);
169 if (f->width > VTFONT_MAXDIMENSION || f->height > VTFONT_MAXDIMENSION ||
170 f->glyph_count > VTFONT_MAXGLYPHS)
171 return (E2BIG);
172
173 /* Not too many mappings. */
174 for (i = 0; i < VFNT_MAPS; i++)
175 if (f->map_count[i] > VTFONT_MAXMAPPINGS)
176 return (E2BIG);
177
178 /* Character 0 must always be present. */
179 if (f->glyph_count < 1)
180 return (EINVAL);
181
182 glyphsize = howmany(f->width, 8) * f->height * f->glyph_count;
183 if (glyphsize > VTFONT_MAXGLYPHSIZE)
184 return (E2BIG);
185
186 /* Allocate new font structure. */
187 vf = malloc(sizeof *vf, M_VTFONT, M_WAITOK | M_ZERO);
188 vf->vf_bytes = malloc(glyphsize, M_VTFONT, M_WAITOK);
189 vf->vf_height = f->height;
190 vf->vf_width = f->width;
191 vf->vf_refcount = 1;
192
193 /* Allocate, copy in, and validate mappings. */
194 for (i = 0; i < VFNT_MAPS; i++) {
195 vf->vf_map_count[i] = f->map_count[i];
196 if (f->map_count[i] == 0)
197 continue;
198 mapsize = f->map_count[i] * sizeof(vfnt_map_t);
199 vf->vf_map[i] = malloc(mapsize, M_VTFONT, M_WAITOK);
200 error = copyin(f->map[i], vf->vf_map[i], mapsize);
201 if (error)
202 goto bad;
203 error = vtfont_validate_map(vf->vf_map[i], vf->vf_map_count[i],
204 f->glyph_count);
205 if (error)
206 goto bad;
207 }
208
209 /* Copy in glyph data. */
210 error = copyin(f->glyphs, vf->vf_bytes, glyphsize);
211 if (error)
212 goto bad;
213
214 /* Success. */
215 *ret = vf;
216 return (0);
217
218 bad: vtfont_unref(vf);
219 return (error);
220 }
221